This study summarizes the preoperative and postoperative clinical and hemodynamic results in 26 patients undergoing simultaneous triple valve (aortic, mitral, tricuspid) replacement (TVR) between 1966-1975. Ten patients who received only mechanical prosthetic replacements (Group I) are compared with fifteen who received porcine xenograft (Hancock) replacements of all atrioventricular valves (Group II). The patient profiles of both groups including sex, age, severity of symptoms, cardiac lesions, and preoperative hemodynamic parameters were similar. Severe cardiac decompensation was evidenced by pulmonary arterial and venous hypertension with low cardiac indices in both groups. Total operative and bypass time and duration of inotropic and respiratory support were shorter, and hemodynamic improvement was better in Group II compared with Group I following TVR. The requirements for temporary pacing and incidence of heart block were greater in Group II. Early mortality was Group I, 33 percent, Group II, 18.8 percent. The late survival rates for operative survivors were Group I, 58 percent and Group II, 93 percent. There have been multiple late complications including thromboembolism in Group I and none in Group II. Four of 7 Group I and 12/13 Group II operative survivors have improved at least 2 functional classes, enabling them to return to employment or resume household duties.